The functionality of bovine milk during acid-induced gelation is governed by the interplay between protein genetic variants and the overall protein composition. This study evaluates the influence of bovine milk κ-casein (κ-CN; AA, AB) and β-casein (β-CN; A1A1, A1A2, A2A2) genetic variants on the microstructure and physicochemical properties of set and stirred yoghurts prepared from 5% (w/w) rehydrated skim milk.The κ-CN(AB) milk contained smaller casein micelles compared to κ-CN(AA), attributed to the larger surface area and higher proportion of κ-CN. Smaller micelles allowed more interaction points for whey protein complexation, leading to the formation of larger protein aggregates and a firmer gel network. This was associated with improved gel strength and lower syneresis after storage in set yoghurts, and increased resistance to shear in stirred yoghurts.While the β-CN genetic variants influenced initial acidification rates and kinetics, results suggest its influence was likely dependent on the β-lactoglobulin (β-Lg) to κ-CN ratio and it is hypothesised that the β-(A1) allele may facilitate more efficient early-stage acidification when β-Lg levels are limited. However, these differences in behaviour observed between milks of varying β-CN genetic variants were not sustained after 24 h of refrigerated storage, as the protein network continued to rearrange towards equilibrium.These results suggest the κ-CN genotype primarily governs yoghurt viscoelastic properties, while β-CN genotype may influence early-stage gelation kinetics. Results also indicate that yoghurt quality is best measured under refrigerated conditions and at least 24 h post-production as measurements taken during fermentation may not reflect the final consumer experience.

Plant-based milk alternatives (PBMAs) are now increasingly used by some consumers in similar ways to cow milk. However, they differ in their physicochemical and sensory properties. Improving PBMAs to better mimic dairy is limited by the time and cost of development trials. Machine learning offers a promising approach to predict optimal formulations without the need for extensive trial and error. In this study, Random Forest regression (RFR) and gradient boosting regression (GBR) models were used to formulate PBMAs (Formulation 1 and 2, respectively) that mimic cow milk. Sensory analysis, viscosity, stability, color, particle size, and headspace volatiles were compared to cow milk to assess model accuracy. Both formulations were sensorially distinct from coconut, oat, soy, almond, pasteurized, and ultra-high temperature (UHT) cow milk, associated with vanilla, caramel, astringent, bitter, metallic, and nutty notes, compared to the sweet, dairy, and coconut notes of dairy. The formulations contained aldehydes, including hexanal and pentanal from soy, although compounds including vanillin, octanal, and 1-pentanol were shared with cow milk. UHT cow (0.68 µm) had the smallest average particle size (D50), followed by Formulation 2 and pasteurized cow (1.04 µm), with Formulation 1 (1.62 µm) as the largest. The UHT and pasteurized cow milk had higher whiteness indices compared with Formulation 1 and Formulation 2. Formulations exhibited faster sedimentation compared to cow milk. The models correctly predicted viscosity and some volatiles. However, predictive performance was limited by the small dataset and restricted access to commercial formulations. A larger dataset and access to formulations would improve model accuracy. PRACTICAL APPLICATIONS: This research demonstrates the potential of predictive modelling for the development of plant-based alternatives to animal-derived ingredients. Such an approach would reduce reliance on trial and error in product development, saving time and development costs while meeting consumer needs.

The global dairy industry has shifted from a commodity-based focus towards precision nutrition where the importance of bioefficacy, function, and structural modification for enhanced performance has emerged. This highlights a need to better understand the role of post-translational modifications within dairy proteins, specifically the functional and biological role of enzymatically attached glycans. This review bridges the gap between the structural elements and chemistry of glycosylated dairy proteins with newly emerging research on the benefits and function of glycosylation. It also examines the recent commercial focus on biomimetic proteins that use glycosylation as structuring tools. This review will cover advances in the isolation and analysis of glycosylated proteins, plus understandings that will allow the industry to harness genetics for enhanced glycosylation, alongside genetic strategies for improved dairy product functionality. It further explores the production of biomimetic proteins through synthetic biology or enzymatic pathways, the development of prebiotic ingredients to support beneficial gut bacteria, and next-generation infant formulas designed to more closely mimic the glycosylation patterns of human milk. This provides a timely overview of how natural or engineered enzymatically attached glycans can create high-value, functional ingredients for a market increasingly defined by optimised performance and precision nutrition.

Abstract Modern food systems produce vast quantities of agro-industrial residues while often failing to deliver nutritionally adequate diets. Public debate frequently frames processed foods as inherently harmful; however, this viewpoint argues that the primary problem lies not in processing itself, but in ingredient design and nutritional intent. Fruit and vegetable peels and pomace, seed cakes, cereal brans, and herbal by-products represent underutilised reservoirs of dietary fibre, protein, minerals, and polyphenols that could meaningfully improve the nutritional quality of processed foods if translational barriers were addressed. We advocate a shift towards ingredient-ready solutions enabled by green extraction, fermentation, and functional structuring. Rather than treating these ingredients and residues as disposal burdens, the agrifood sector should harness them as high value opportunities for healthier diets, contributing to sustainability and the broader bioeconomy. Regulatory clarity, transparent labelling, and proactive science communication are identified as decisive enablers for adoption. This Viewpoint provides a strategic analysis of the translational barriers preventing industry adoption and proposes a shift to reposition their use as functional tools for the nutritional reformulation of commercial food products. If food science aims to reform contemporary diets, the next generation of ingredients must arise not from scarcity, but from what currently goes to waste.

Stirred yoghurts were prepared using experimental milks with 1.5-12.0 % (w/w) total protein and consisting of either rehydrated skim milk ('control') or rehydrated skim milk and pea protein isolate in combination (2:1, 'hybrid'). The average d4,3 and d90 particle size was similar for the 1.5 and 3.0 % (w/w) hybrid and control yoghurts, but differed at higher concentrations, with smaller particles found in the 6-12 % (w/w) hybrid yoghurts compared to the corresponding control. Despite this, the particle size distribution span was similar across yoghurts within each protein concentration set. Hybrid yoghurts prepared from 6-12 % (w/w) experimental milks had lower apparent viscosities and yield stress compared to the control at the same protein concentration. SEM imaging and the physicochemical data indicate that pea protein particles act as inactive fillers within the stranded skim milk protein network, leading to the development of weaker and less structured gels, hence a lower apparent viscosities and yield stress. Higher protein hybrid yoghurts were perceived less lumpy but chalkier than their control counterparts. All yoghurts were similar for smoothness, adhesiveness, and oily film regardless of protein concentration. All other perceived sensorial parameters were similar for yoghurts within each protein concentration set, indicating that the changes in the microstructure due to the introduction of pea protein did not impact key textural attributes. Yoghurts were compared to products of different levels as per the International Dysphagia Diet Standardisation Initiative standards to estimate their ease to swallow and suitability for people with dysphagia, with promising comparisons at Levels 2-4.

Pea protein is a promising ingredient for plant-based cheese production but has poor consumer acceptance due to intrinsic beany flavors. Fermentation could potentially decrease these off-flavors while also producing desirable cheese-like aromas. Pea protein emulsion gels were fermented using four different bacterial blends for 16 weeks with and without the crosslinking enzyme transglutaminase. The volatile organic compound (VOC) profiles were assessed by GC-MS and the peptide profile was measured by LC-MS/MS during storage. VOC production was mainly affected by the composition of the bacterial blends, followed by storage time. Crosslinking of the protein gel structure had minimal impact on VOC production. The peptide-level profiling revealed that crosslinking can reduce peptide size and the production of bitterness-like peptides in some blends. This study provides insights into the effect of bacterial blends, storage time, and enzymatic crosslinking on the production of volatile components and peptides related to aroma and peptide profiles for pea protein.

Plant-based milk alternatives (PBMA) have emerged as popular substitutes for cow milk, driven by health, environmental, and ethical considerations. However, their ability to replicate the sensory and physicochemical properties of dairy remains a critical challenge for industry. This review critically examines the extent to which almond, soy, and oat PBMA replicate key sensory attributes of ultra-high temperature (UHT) full cream cow milk, focusing on appearance, texture, and flavour. Furthermore, it explores the relationship between these sensory attributes and the physicochemical properties of PBMA to elucidate the underlying reasons for the observed differences. A comparative analysis of compositional differences reveals fundamental limitations linked to plant protein functionality, carbohydrate structure, fat composition, and mineral fortification, all of which contribute to disparities in creaminess, mouthfeel, colour, and flavour. Technological strategies such as particle size reduction, enzymatic hydrolysis, and flavour masking have improved specific attributes, yet no PBMA fully replicates the holistic sensory experience of dairy. Emerging approaches, including blended formulations, precision fermentation, and artificial intelligence (AI)-driven optimisation, show promise in narrowing these gaps. Nonetheless, a complete replication of UHT cow milk remains elusive, highlighting the need for continued research and innovation to either approximate dairy properties more closely or enhance PBMA’s unique qualities to drive consumer acceptance.

Descriptive sensory analysis discriminated between the appearance, aroma, flavor, taste and texture of Cheddar cheese samples prepared from milk varying in fat globule size; small milk fat globule milk (SMM, d(4,3) = 2.76 +/- 0.07 mu m), large milk fat globule milk (LMM, d4,3 = 5.07 +/- 0.06 mu m) and Control (d(4,3) = 3.91 +/- 0.09 mu m), over a six-month maturation period. Significant differences were measured between SMM, LMM and the Control as each cheese matured, where SMM was the most different across all parameters examined. SMM was lowest in color intensity (34.6 < 38.8-47.0), firmness (29.4 < 36.1-47.7), and fracturability (24.5 < 28.8-30.7), and highest in cohesiveness (57.0 > 39.8-45.8), adhesiveness (52.9 > 39.0-45.4), and smoothness (50.4 > 37.9-44.0). Moreover, SMM was more intense than the Control in cultured odor (34.9 > 29.6-30.6) and flavor (45.5 > 34.9-36.2), rancid (23.3 > 16.0-18.6) and metallic (17.7 > 14.3) flavor, salty taste (45.7 > 40.3-40.5) and aftertaste (38.5 > 34.9-35.8), sour (36.3 > 28.9) and umami taste (19.6 > 16.4); attributes that align with the degree of maturation. LMM showed similar differences to the Control, but was firmer (36.1 > 29.4), less cohesive (45.8 < 57.0), adhesive (45.4 < 52.9) and smooth (44.0 < 50.4) and had a less intense cultured odor (31.5 < 34.9) than SMM. An increase in salty taste was associated with a decrease in cheese firmness (-0.91, p < 0.0001). These results could provide process-driven solutions that allow the dairy industry to decrease maturation time or create differentiated cheese products to meet specific consumer tastes or function.

D2O, an isotope of H2O, is commonly used as a solvent in neutron scattering; the large difference in scattering length density between H and D can provide better contrast between the sample and the solvent. However, this is of concern for studies using enzymes as the use of D2O can influence protein interactions (due to differences in hydrogen bonding) and is therefore expected to affect the function, activity and solubility of enzymes. Neutron-based in vitro digestion assays on proteins, including those found in food or as oral protein and peptide drugs, often involve different solvents or pH conditions where the activity of the digestive enzyme may not be optimal. Herein, we investigate the structure and activity of the main gastric protease, porcine pepsin, in both H2O and D2O at pH values in the range 1 – 8. We showed that the activity of pepsin was lower in D2O, although the relative change in activity with pH was similar for both solvents. We demonstrated using a combination of SAXS and CD that this relative change in activity was not related to any structural change within the protein but was, rather, linked to relative changes in solubility of the protein.

The effects of κ‐casein (κ‐CN) and β‐casein (β‐CN) genetic variant and κ‐CN glycosylation degree (GD, low or high) on interfacial and foaming properties of bovine skim milk were investigated. No significant effect was measured for milks with different ĸ‐CN and β‐CN genetic variants. However, milks of higher GD exhibited lower surface tension, enhanced foamability and differences in secondary protein structure compared to lower GD skim milks. Glycan attachment is believed to affect surface activity and the spread and packing of protein at the foam bubble liquid–air interface, leading to differences in foaming performance.

This study investigated the individual and combined effects of ĸ-Casein (ĸ-CN; AA, AB, BB), β-Casein (β-CN; A1A1, A1A2, A2A2) and high and low ratios of glycosylated ĸ-CN to total ĸ-CN, referred to as the glycosylation degree (GD), on bovine cream whipping properties. The genetic variants of individual cows were identified using reversed-phase high-performance liquid chromatography (RP-HPLC) and verified through liquid chromatography-mass spectrometry (LC-MS). A previously discovered relationship between days-in-milk and GD was validated and used to obtain high and low GD milk. Whipped creams were created through the mechanical agitation of fat standardised cream from milk of different ĸ-CN, β-CN, and GD combinations, and whipping properties (the ability to whip, overrun, whipping time and firmness) were evaluated. No significant correlation was measured in whipping properties for cream samples from milks with different ĸ-CN and β-CN genetic variants. However, 80 % of samples exhibiting good whipping properties (i.e., the production of a stiffened peak) were from milk with low GD suggesting a correlation between whipping properties and levels of glycosylation. Moreover, cream separated from skim milk of larger casein micelle size showed superior whipping properties with shorter whipping times (<5 min), and higher firmness and overrun. Milk fat globule (MFG) size, on the other hand, did not affect whipping properties. Results indicate that the GD of κ-CN and casein micelle size may play a role in MFG adsorption at the protein and air interface of air bubbles formed during whipping; hence, they govern the dynamics of fat network formation and influencing whipping properties.

The objective of this study was to demonstrate the feasibility of producing a powdered, multi-nutrient breast milk fortifier made from donated human milk with a target energy (400 kcal 100 g-1 powder) and protein (40 g protein 100 g-1 powder) composition, supplementation of selected micronutrients, and acceptable solubility and osmolality for clinical use. Three combinations of ultrafiltration (UF) and diafiltration (DF) steps, using either a polyethersulphone (PES) or polyvinylidene fluoride (PVDF) membrane with 50 kDa molecular mass cut-off, were compared to determine the most efficient process to achieve the target product composition. A process combining one UF and two DF steps using the PVDF membrane was found to be most efficient, resulting in a freeze-dried product with a final average composition of protein, fat and carbohydrates of 40.7, 11.3 and 47.1 g 100 g-1, respectively. (c) 2024 Elsevier Ltd. All rights reserved.

In recent years, small and ultra-small angle scattering techniques, collectively known as small angle scattering (SAS) have been used to study various food structures during the digestion process. These techniques play an important role in structural characterisation due to the non-destructive nature (especially when using neutrons), various in situ capabilities and a large length scale (of 1 nm to similar to 20 mu m) they cover. The application of these techniques in the structural characterisation of dairy products has expanded significantly in recent years. Casein, a major dairy protein, forms the basis of a wide range of gel structures at different length scales. These gel structures have been extensively researched utilising scattering techniques to obtain structural information at the nano and micron scale that complements electron and confocal microscopy. Especially, neutrons have provided opportunity to study these gels in their natural environment by using various in situ options. One such example is understanding changes in casein gel structures during digestion in the gastrointestinal tract, which is essential for designing personalised food structures for a wide range of food-related diseases and improve health outcomes. In this review, we present an overview of casein gels investigated using small angle and ultra-small angle scattering techniques. We also reviewed their digestion using newly built setups recently employed in various research. To gain a greater understanding of micro and nano-scale structural changes during digestion, such as the effect of digestive juices and mechanical breakdown on structure, new setups for semi-solid food materials are needed to be optimised.

The evolving structure of protein-based foods during the digestion process is critical to the release of nutrients. However, traditional in vitro monitoring of the gel micro- and nano-structure during digestion involves analysing sample aliquots taken at different digestion time periods. This can pose issues for some gels, such as casein-based gels, as they are sensitive to sample manipulation and environmental changes. Herein, a newly developed flow setup was utilised to monitor (at the micro- and nano-length scales) the gel protein network of rennet-induced (RG) and transglutaminase-induced acid gels (TG) in situ and in real-time during simulated gastric digestion using ultra-small and small-angle neutron scattering (USANS and SANS). The proteolysis kinetics of the gels were investigated at two different pepsin enzyme concentrations (2000 and 8000 U mL-1) and in two different solvent environments (H2O and D2O). Results indicate that the flowing in situ system had a greater effect on the microstructural breakdown of TG relative to the acid-sensitive RG, compared to the traditional static method. This is the first in situ digestion study observing the structural changes of large protein gel particles with USANS or SANS in real-time. Our findings advance the understanding of the kinetics of casein gel disintegration under simulated conditions of gastric digestion relating to pepsin enzyme concentration and solvent environment, and critically, the utilisation of a new in situ and real-time setup for neutron studies.

The processes for extracting and refining edible oils are well-established in industry at different scales. However, these processing lines encounter inefficiencies and oil losses when recovering crude or refined oil. Palm oil and olive oil extraction methods are used mainly as a combination of physical, thermal, and centrifugal methods to recover crude oil, which results in oil losses in the olive pomace or in palm oil effluents. Seed oils generally require a seed steam conditioning, and cooking stage, followed by physical oil recovery through an inefficient expeller. Most of the crude oil remaining in the expeller cake is then recovered by hexane. Crude seed oil is further refined in stages that also undergo oil losses. This chapter provides an overview of innovative technologies using microwave, ultrasound, megasonic and pulsed electric field energies, which can be used in the above-mentioned crude and refined oil processes to improve oil recovery. This chapter describes traditional palm oil, olive oil, and seed oil processes, as well as the specific process interventions that have been tested with these technologies. The impact of such technology interventions on oil quality is also summarized.

The aim of this study was to assess how transglutaminase (TG) impacts the microstructure, texture, and rheological properties of fermentation-induced pea protein emulsion gels.

In order to explore the functions of glycosylation of kappa-Casein (kappa-CN) in bovine milk, unglycosylated (UG) and twice glycosylated (2G) forms of kappa-CN B were purified by selective precipitation followed by anion exchange chromatography from kappa-CN BB milk and tested for their amyloid fibril formation and morphology, oligomerisation states and protein structure. The diameter of self-assembled kappa-CN B aggregates of both glyco-form were shown for the first time to be in the same 26.0-28.7 nm range for a 1 mg mL(-1) solution. The presence of two bound glycans in the protein structure of 2G kappa-CN B led to a greater increase in the maximum amyloid fibril formation rate with increasing protein concentration and a difference in both length (82.0 +/- 29.9 vs 50.3 +/- 13.7 nm) and width (8.6 +/- 2.1 vs 13.9 +/- 2.5 nm) for fibril morphology compared to UG kappa-CN B. The present results suggest that amyloid fibril formation proceeds at a slow but steady rate via the self-assembly of dissociated, monomeric kappa-CN B proteins at concentrations of 0.22-0.44 mg mL(-1). However amyloid fibril formation proceeds more rapidly via the assembly of either aggregated kappa-CN present in a micelle-like form or dissociated monomeric kappa-CN, packed into reorganised formational structures above the critical micellar concentration to form fibrils of differing width. The degree of glycosylation has no effect on the polarity of the adjacent environment, nor non-covalent and disulphide interactions between protein molecules when in the native form. Yet glycosylation can influence protein folding patterns of kappa-CN B leading to a reduced tryptophan intrinsic fluorescence intensity for 2G compared to UG kappa-CN B. These results demonstrate that glycosylation plays an important role in the modulation of aggregation states of kappa-CN and contributes to a better understanding of the role of glycosylation in the formation of amyloid fibrils from intrinsically disordered proteins.

Limited studies in the literature have compared in vitro dynamic and in vitro static protocols for modelling the gastric digestive process of food systems. This experiment explores the differences between two different in vitro approaches to the devolution of a transglutaminase-induced acid gel (TG, pH 5.1-5.3) and rennet-induced gel (RG, pH 6.5-6.7). Gels were exposed to a simulated oral phase, followed by either the dynamic DIDGI (R) or static COST action INFOGEST protocol to simulate gastric conditions. Protein hydrolysis was evident from 15 min onwards for TG exposed to the dynamic protocol where levels continued to increase at a steady rate. In contrast, RG exhibited a notable lag-phase before levels increased from around 60 min onwards. Under the static protocol, protein hydrolysis was observed for both TG and RG upon exposure to the gastric environment which continued to increase over time. Despite these differences, similar levels of protein hydrolysis were found for TG and RG at the gastric endpoint using either protocol demonstrating that both the dynamic DIDGI (R) and static COST action INFOGEST methods provide a suitable and comparable environment for the in vitro digestion of casein protein under simulated gastric conditions.

Whilst there are only four genes that encode caseins found in bovine milk, there is a vast array of naturally occurring variants of each protein arising from both genetic polymorphisms and post-translational modification. Effects of the different casein genetic variants on production traits, composition and functional properties of milk have been discovered over the last two decades, and their potential use as an active ingredient in products for improved health outcomes has formed the basis for consumer marketing. Research focused on casein post-translational modifications is an emerging area, and the influence of phosphorylation and glycosylation modifications on the compositional and functional properties of milk is not yet fully elucidated. This review article outlines the influence of casein genetic variants, phosphorylation and glycosylation on the structure of casein and how the properties of certain casein variants associate with human nutrition and the physicochemical and sensory characteristics of dairy products.

Small and Ultra Small Angle Neutron Scattering (SANS and USANS) are commonly used techniques for the nano and microstructural characterisation of systems such as polymers, gels, and aggregates. In many cases, for practical purposes, disruption of the larger structures into smaller particles may be necessary to meet the requirements of the specific sample environment used. However, a lack of knowledge about its effect on the nano and microstructure prevents the adoption of this simple approach. In our study, we used a newly developed recirculated flow set-up designed for the in-situ measurement of blended transglutaminase-induced acid gels (TG). The average gel size reduction of distributions examined herein (d50; 1020, 462, and 294 mu m) did not noticeably alter the integrity of gel structure at the interior of the particle. This study validates the proposed approach as an effective way to examine structural elements at a micro-or nanoscale using in-situ neutron scattering techniques.